1. Field of the Invention
The present invention relates to a three-dimensional liquid crystal display system and method thereof, and more particularly, to a liquid crystal display system which adjusts a backlight to generate a three-dimensional image effect and method thereof.
2. Description of the Prior Art
In stereoscopic image display technologies, a pair of shutter glasses is usually used with a display for sequentially displaying left eye images and right eye images, so that an observer may perceive three-dimensional images. However, in existing techniques, the observer often sees ghost shadows when the stereoscopic image display transitions from a left eye image to a right eye image. More specifically, such ghost shadows are generated due to the fact that a right eye image displayed on the LCD has not entirely disappeared after a left shutter of the pair of shutter glasses is turned on, whereby the observer sees part of the right eye image in his/her left eye. Such ghost shadows also occur due to the fact that a left eye image displayed on the LCD has not disappeared after a right shutter of the pair of shutter glasses is turned on, whereby the observer sees part of the left eye image in his/her right eye.
In the prior art methods for displaying three-dimensional images, black frame insertion is a technique used to prevent generation of the ghost shadows. Please refer to FIG. 1. FIG. 1 is a diagram illustrating a display method for use in a liquid crystal display (LCD) combined with a pair of shutter glasses 120. As shown in FIG. 1, the LCD sequentially displays frames 102-116. The frames 102-116 include left eye image frames 102, 110, right eye image frames 106, 114, and black frames 104, 108, 112, and 116. In FIG. 1, tv is a time interval required for the LCD to display one frame. The pair of shutter glasses 120 coordinates with the frames 102-116 shown in FIG. 1 to switch the left shutter and the right shutter. As shown in FIG. 1, when the left eye image frame 102 is displayed, the left shutter is turned on and the right shutter is turned off, so the left eye of the observer may receive the left eye image frame on the LCD; when the right eye image frame 106 is displayed, the left shutter is turned off and the right shutter is turned on, so the right eye of the observer may receive the right eye image frame on the LCD. Similarly, when the left eye image frame 110 is displayed, the left shutter is turned on and the right shutter is turned off; when the right eye image frame 114 is displayed, the left shutter is turned off and the right shutter is turned on. By the shutter glasses 120 switching the left shutter and the right shutter in sync with the frames 102-116, the left eye and the right eye of the observer may respectively receive the left eye image signals and the right eye image signals, so that the observer may perceive a three-dimensional image effect through the frames 102-116. The LCD does not display each image in its entirety at one instant, but instead uses a horizontal scan method, such that images are altered progressively. Therefore, a black frame is inserted between a right eye image frame and a left eye image frame in order to prevent the ghost shadows resulting from right eye images from being received by the left eye of a user, and vision of the user being confused.
However, there are still many disadvantages in the prior art. For example, the prior art of inserting black frames cuts the frame rate experienced by the user to only ¼ of the display frame rate. If the display frame rate is 120 Hz, the display utilizing the black frame insertion can only support display of three-dimensional images at 30 Hz. That is to say, the frames 102 and 110 separated by three frames are left eye image frames and the frames 106 and 114 separated by three frames are right eye image frames.